Composer Errollyn Wallen has an eclectic style rooted in popular song but not classifiable as crossover. Many of her works are oriented toward the voice, but she has also composed in many traditional classical genres.

Wallen was born April 10, 1958, in Belize City, then part of the colony of British Honduras. Her brother is jazz trumpeter Byron Wallen. When Errollyn was two, her family moved to London. Errollyn's parents moved on to New York, where Errollyn studied at the Dance Theater of Harlem, but she was mostly raised in England by an aunt and uncle. Wallen attended Goldsmiths College at the University of London and King's College, London, studying composition. She went on for an MPhil degree at King's College, Cambridge. During her student years, she founded the group Ensemble X, whose members had the credo that they did not break down barriers in music because they did not see any.

Wallen began to find success with chamber music early in her career, penning a Trio for two flutes and vibraphone as early as 1982. In 1994, percussionist Colin Currie commissioned from Wallen a Concerto for percussion and orchestra, which he played at the finals of the BBC Young Musician Competition. The work was performed at the 1998 BBC Proms, making Wallen the first Black woman to have a piece performed at the Proms, and again at the 2006 Cervantino Festival in Mexico. Wallen has written numerous songs, including the cycle Are You Worried About the Rising Cost of Funerals, for soprano and string quartet. Many of her songs are influenced by popular music. She has written several operas, including The Silent Twins (2007) and Another America, a multi-part operatic project. Wallen has also composed Carbon 12: A Choral Symphony, as well as the 40-voice choral work When the Wet Wind Sings. Her orchestral works include Mighty River (2017), commemorating the 200th anniversary of the abolition of slavery in Britain; it was premiered by the Philharmonia Orchestra conducted by Martyn Brabbins.

More than 20 of Wallen's works have been recorded, and she has issued two albums under her name, The Girl in My Alphabet (2002) and Errollyn (2004), on the Avie label. In 2007, Wallen was appointed Member of the Order of the British Empire, and she became Commander of the Order of the British Empire in 2020. ~ James Manheim, Rovi